普通玉米和特用玉米的SSR标记聚类

利用SSR标记研究了64份玉米自交系（包括普通玉米和特用玉米自交系）的亲缘关系。用30对扩增带型稳定的SSR引物，从供试材料中检测出116个等位基因变异，每对引物检测出等位基因2~10个，平均3.87个。SSR引物的PIC介于0.306~0.893之间，平均多态性信息量为0.717。按UPGMA方法对供试自交系进行聚类，以遗传距离0.586为基准，可将材料划分为11类。64份自交系的SSR标记聚类分析表明，普通玉米与特用玉米糯玉米、甜玉米、爆裂玉米等并不能严格地各自划为一类，只有亲缘关系较近的特用玉米自交系聚在一起，有些特用玉米与普通玉米聚在一起，部分特用玉米具有丰富的普通玉米种质资源遗传背景。特用玉米自交系间的遗传距离与普通玉米自交系间的遗传距离差异达到0.01的极显著水平。此外，不同类型特用玉米间、特用玉米与普通玉米间的遗传差异较大，特用玉米在进化和选育过程中积累并保存了丰富的遗传变异。

Cluster Analysis for Normal and Special Maize Inbreds with SSR Markers

The genetic relationship of 64 maize inbred lines （including normal and special maize inbred lines）was studied by simple sequence repeats (SSRs) marker. 30 SSR primers giving stable amplified band pattern detected 116 alleles among the lines tested. The average number of alleles per SSR locus was 3.87 with a range of 2 ~ 10. The value of polymorphism information content(PIC) for each SSR locus varied from 0.306 to 0.893 with an average of 0.717.According to UPGMA method, with Genetic Distance=0.586 as benchmark, the tested materials were compartmentalized to 11 genus distinctly. Clustering analysis of 64 maize inbred lines showed that normal and special maize couldn’t be compartmentalized to one genus each strictly, only the materials with close genetic relationship coul be gathered closely. And many special maize inbred lines gather together with normal maize inbred lines. The study also showed that some special maize inbred lines own strong genetic background of normal maize. The difference in mean genetic distance between special and normal maize was at 0.01 significant level. Between special and normal maize, or among different kinds of special maize, genetic diversity were quite large. Special maize inbred lines in the program of evolution and breeding may have accumulated and stored much genetic aberrance.